Question

Lithium hydroxide, LiOH, reacts with carbon dioxide to produce
lithium carbonate, Li2CO3. The chemical equation for this reaction
is:
2LiOH(s)+CO2(2)-->Li2CO3(s)+H2O(l)
Carbon dioxide is produced every time a person exhales. Some NASA
spacecraft rely on this lithium hydroxide reaction to remove
exhaled carbon dioxide from the air inside the spacecraft. Air is
pumped through a filter containing lithium hydroxide. Inside the
filter, carbon dioxide is removed from the air when it reacts with
lithium hydroxide to produce lithium carbonate.
a) Describe why the amount of lithium hydroxide present limits the
amount of time the astronauts can spend in space?
b) Sodium hydroxide, NaOH, reacts the same as lithium hydroxide and
is much cheaper. However, sodium hydroxide is about 40 percent
heavier than lithium hydroxide. Why do you think NASA uses LiOH on
its space missions?